Patent application number | Description | Published |
20090049226 | STALE TRACK INITIALIZATION IN A STORAGE CONTROLLER - Deleting a data volume from a storage system and freeing its storage space to make it available to be allocated to a new volume is accomplished by only zeroing associated metadata for the tracks contained in the freed storage space which is then reused in a new volume allocation and an attempt is made by the new volume to read a first record R | 02-19-2009 |
20090049265 | STALE TRACK INITIALIZATION IN A STORAGE CONTROLLER - Deleting a data volume from a storage system and freeing its storage space to make it available to be allocated to a new volume is accomplished by only zeroing associated metadata for the tracks contained in the freed storage space which is then reused in a new volume allocation and an attempt is made by the new volume to read a first record R | 02-19-2009 |
20100325356 | NONVOLATILE STORAGE THRESHOLDING - Embodiments for facilitating data transfer between a nonvolatile storage (NVS) write cache and a pool of target storage devices are provided. Each target storage device in the pool of target storage devices is determined as one of a hard disk drive (HDD) and a solid-state drive (SSD) device, and classified into one of a SSD rank group and a HDD rank group. If no data is received in the NVS write cache for a predetermined time to be written to a target storage device classified in the SSD rank group, a threshold of available space in the NVS write cache is set to allocate at least a majority of the available space to the HDD rank group. Upon receipt of a write request for the SSD rank group, the threshold of the available space is reduced to allocate a greater portion of the available space to the SSD rank group. | 12-23-2010 |
20120254547 | MANAGING METADATA FOR DATA IN A COPY RELATIONSHIP - Provided are a computer program product, system, and method for managing metadata for data in a copy relationship copied from a source storage to a target storage. Information is maintained on a copy relationship of source data in the source storage and target data in the target storage. The source data is copied from the source storage to the cache to copy to target data in the target storage indicated in the copy relationship. Target metadata is generated for the target data comprising the source data copied to the cache. An access request to requested target data comprising the target data in the cache is processed and access is provided to the requested target data in the cache. A determination is made as to whether the requested target data in the cache has been destaged to the target storage. The target metadata for the requested target data in the target storage is discarded in response to determining that the requested target data in the cache has not been destaged to the target storage. | 10-04-2012 |
20120303888 | DESTAGING OF WRITE AHEAD DATA SET TRACKS - Exemplary methods, computer systems, and computer program products for efficient destaging of a write ahead data set (WADS) track in a volume of a computing storage environment are provided. In one embodiment, the computer environment is configured for preventing destage of a plurality of tracks in cache selected for writing to a storage device. For a track N in a stride Z of the selected plurality of tracks, if the track N is a first WADS track in the stride Z, clearing at least one temporal bit for each track in the cache for the stride Z minus 2 (Z−2), and if the track N is a sequential track, clearing the at least one temporal bit for the track N minus a variable X (N−X). | 11-29-2012 |
20120303898 | MANAGING UNMODIFIED TRACKS MAINTAINED IN BOTH A FIRST CACHE AND A SECOND CACHE - Provided are a computer program product, system, and method for managing unmodified tracks maintained in both a first cache and a second cache. The first cache has unmodified tracks in the storage subject to Input/Output (I/O) requests. Unmodified tracks are demoted from the first cache to a second cache. An inclusive list indicates unmodified tracks maintained in both the first cache and a second cache. An exclusive list indicates unmodified tracks maintained in the second cache but not the first cache. The inclusive list and the exclusive list are used to determine whether to promote to the second cache an unmodified track demoted from the first cache. | 11-29-2012 |
20120303899 | MANAGING TRACK DISCARD REQUESTS TO INCLUDE IN DISCARD TRACK MESSAGES - Provided are a computer program product, system, and method for managing track discard requests to include in discard track messages. A backup copy of a track in a cache is maintained in the cache backup device. A track discard request is generated to discard tracks in the cache backup device removed from the cache. Track discard requests are queued in a discard track queue. In response to detecting that a predetermined number of track discard requests are queued in the discard track queue while processing in a discard multi-track mode, one discard multiple tracks message is sent indicating the tracks indicated in the queued predetermined number of track discard requests to the cache backup device instructing the cache backup device to discard the tracks indicated in the discard multiple tracks message. In response to determining a predetermined number of periods of inactivity while processing in the discard multi-track mode, processing the track discard requests is switched to a discard single track mode. | 11-29-2012 |
20120324173 | EFFICIENT DISCARD SCANS - Exemplary method, system, and computer program product embodiments for performing a discard scan operation are provided. In one embodiment, by way of example only, a plurality of tracks is examined for meeting criteria for a discard scan. In lieu of waiting for a completion of a track access operation, at least one of the plurality of tracks is marked for demotion. An additional discard scan may be subsequently performed for tracks not previously demoted. The discard and additional discard scans may proceed in two phases. Additional system and computer program product embodiments are disclosed and provide related advantages. | 12-20-2012 |
20130145100 | MANAGING METADATA FOR DATA IN A COPY RELATIONSHIP - Provided is a method for managing metadata for data in a copy relationship copied from a source storage to a target storage. Information is maintained on a copy relationship of source data in the source storage and target data in the target storage. The source data is copied from the source storage to the cache to copy to target data in the target storage indicated in the copy relationship. Target metadata is generated for the target data comprising the source data copied to the cache. An access request to requested target data comprising the target data in the cache is processed and access is provided to the requested target data in the cache. The target metadata for the requested target data in the target storage is discarded in response to determining that the requested target data in the cache has not been destaged to the target storage. | 06-06-2013 |
20130166837 | DESTAGING OF WRITE AHEAD DATA SET TRACKS - Exemplary methods, computer systems, and computer program products for efficient destaging of a write ahead data set (WADS) track in a volume of a computing storage environment are provided. In one embodiment, the computer environment is configured for preventing destage of a plurality of tracks in cache selected for writing to a storage device. For a track N in a stride Z of the selected plurality of tracks, if the track N is a first WADS track in the stride Z, clearing at least one temporal bit for each track in the cache for the stride Z minus 2 (Z−2), and if the track N is a sequential track, clearing the at least one temporal bit for the track N minus a variable X (N−X). | 06-27-2013 |
20130198461 | MANAGING TRACK DISCARD REQUESTS TO INCLUDE IN DISCARD TRACK MESSAGES - Provided is a method for managing track discard requests. A backup copy of a track in a cache is maintained in a cache backup device. A track discard request is generated to discard tracks in the cache backup device removed from the cache. Track discard requests are queued in a discard track queue. If a predetermined number of track discard requests are queued in the discard track queue while processing in a discard multi-track mode, one discard multiple tracks message is sent to the cache backup device indicating the tracks indicated in the queued predetermined number of track discard requests to instruct the cache backup device to discard the tracks indicated in the discard multiple tracks message. If a predetermined number of periods of inactivity while processing in the discard multi-track mode, processing the track discard requests is switched to a discard single track mode. | 08-01-2013 |
20130219124 | EFFICIENT DISCARD SCANS - A plurality of tracks is examined for meeting criteria for a discard scan. In lieu of waiting for a completion of a track access operation, at least one of the plurality of tracks is marked for demotion. An additional discard scan may be subsequently performed for tracks not previously demoted. The discard and additional discard scans may proceed in two phases. | 08-22-2013 |
20140082256 | RECOVERY FROM CACHE AND NVS OUT OF SYNC - For cache/data management in a computing storage environment, incoming data segments into a Non Volatile Storage (NVS) device of the computing storage environment are validated against a bitmap to determine if the incoming data segments are currently in use. Those of the incoming data segments determined to be currently in use are designated to the computing storage environment to protect data integrity. | 03-20-2014 |
20140082283 | EFFICIENT CACHE VOLUME SIT SCANS - A processor, operable in a computing storage environment, allocates portions of a Scatter Index Table (SIT) disproportionately between a larger portion dedicated for meta data tracks, and a smaller portion dedicated for user data tracks, and processes a storage operation through the disproportionately allocated portions of the SIT using an allocated number of Task Control Blocks (TCB). | 03-20-2014 |
20140082294 | MANAGEMENT OF DESTAGE TASKS WITH LARGE NUMBER OF RANKS - A processor, operable in a computing storage environment, for each rank in a storage management device in the computing storage environment, allocates a lower maximum count, and a higher maximum count, of Task Control Blocks (TCBs) to be implemented for performing a storage operation, and performs the storage operation using up to the lower maximum count of TCBs, yet only allows those TCBs above the lower maximum count to be allocated for performing the storage operation satisfying at least one criterion. | 03-20-2014 |
20140082303 | MANAGEMENT OF DESTAGE TASKS WITH LARGE NUMBER OF RANKS - A processor, operable in a computing storage environment, for each rank in a storage management device in the computing storage environment, allocates a lower maximum count, and a higher maximum count, of Task Control Blocks (TCBs) to be implemented for performing a storage operation, and performs the storage operation using up to the lower maximum count of TCBs, yet only allows those TCBs above the lower maximum count to be allocated for performing the storage operation satisfying at least one criterion. | 03-20-2014 |
20140095762 | FUZZY COUNTERS FOR NVS TO REDUCE LOCK CONTENTION - A system for data management in a computing storage environment includes a processor device, operable in the computing storage environment, that divides a plurality of counters tracking write and discard storage operations through Non Volatile Storage (NVS) space into first, accurate, and second, fuzzy, groups where the first, accurate, group is one of incremented and decremented per each write and discard storage operation, while the second, fuzzy, group is one of incremented and decremented on a more infrequent basis as compared to the first, accurate group. | 04-03-2014 |
20140095763 | NVS THRESHOLDING FOR EFFICIENT DATA MANAGEMENT - For data management by a processor device in a computing storage environment, a threshold for an amount of Non Volatile Storage (NVS) space to be consumed by any particular logically contiguous storage space in the computing storage environment is established based on at least one of a Redundant Array of Independent Disks (RAID) type, a number of point-in-time copy source data segments in the logically contiguous storage space, and a storage classification. | 04-03-2014 |
20140095787 | NVS THRESHOLDING FOR EFFICIENT DATA MANAGEMENT - For data management by a processor device in a computing storage environment, a threshold for an amount of Non Volatile Storage (NVS) space to be consumed by any particular logically contiguous storage space in the computing storage environment is established based on at least one of a Redundant Array of Independent Disks (RAID) type, a number of point-in-time copy source data segments in the logically contiguous storage space, and a storage classification. | 04-03-2014 |
20140095811 | FUZZY COUNTERS FOR NVS TO REDUCE LOCK CONTENTION - A system for data management in a computing storage environment includes a processor device, operable in the computing storage environment, that divides a plurality of counters tracking write and discard storage operations through Non Volatile Storage (NVS) space into first, accurate, and second, fuzzy, groups where the first, accurate, group is one of incremented and decremented per each write and discard storage operation, while the second, fuzzy, group is one of incremented and decremented on a more infrequent basis as compared to the first, accurate group. | 04-03-2014 |
20150212739 | MANAGEMENT OF EXTENT CHECKING IN A STORAGE CONTROLLER DURING COPY SERVICES OPERATIONS - A storage controller receives a request to avoid extent conflict checking from a host application executing in a host that is coupled to the storage controller. In response to receiving a request, a host I/O process that executes in the storage controller to satisfy I/O requests from the host application opportunistically releases a track of an extent to a copy services process at an earliest point in time when the track of the extent is longer needed by the host I/O process and is needed by the copy services process. | 07-30-2015 |
20150339182 | FUZZY COUNTERS FOR NVS TO REDUCE LOCK CONTENTION - A system for data management in a computing storage environment includes a processor device, operable in the computing storage environment, that divides a plurality of counters tracking write and discard storage operations through Non Volatile Storage (NVS) space into first, accurate, and second, fuzzy, groups where the first, accurate, group is one of updated on a per operation basis, while the second, fuzzy, group is one of updated on a more infrequent basis as compared to the first, accurate group. | 11-26-2015 |
20160055091 | FUZZY COUNTERS FOR NVS TO REDUCE LOCK CONTENTION - A method for data management in a computing storage environment includes a processor device, operable in the computing storage environment, that divides a plurality of counters tracking write and discard storage operations through Non Volatile Storage (NVS) space into first, accurate, and second, fuzzy, groups where the first, accurate, group is one of updated on a per operation basis, while the second, fuzzy, group is one of updated on a more infrequent basis as compared to the first, accurate group. | 02-25-2016 |
20160085673 | CONCURRENT UPDATE OF DATA IN CACHE WITH DESTAGE TO DISK - Mechanisms for concurrent update of data in cache with destage of data from the cache to disk by a processor device. A second copy of the data is established in the cache and on a cache directory. A first copy of the data and the second copy of the data are adjacently ordered in the cache directory. One of the first and second copies is held for an update operation so as to include a latest data modification, while the remaining copy concurrently is used for a destage operation to disk. | 03-24-2016 |
Patent application number | Description | Published |
20080201523 | PRESERVATION OF CACHE DATA FOLLOWING FAILOVER - In a data storage subsystem with disk storage and a pair of clusters, one set of DASD fast write data is in cache of one cluster and in non-volatile data storage of the other. In response to a failover of one of the pair of clusters to a local cluster, the local cluster converts the DASD fast write data in local cache to converted fast write data to prioritize the converted data for destaging to disk storage. In response to failure to destage, the local cluster allocates local non-volatile storage tracks and emulates a host adapter to store the converted fast write data by the local non-volatile storage, reconverting the converted fast write data of the non-volatile storage to local DASD fast write data stored in the local non-volatile storage and stored in the local cache storage. | 08-21-2008 |
20080250210 | COPYING DATA FROM A FIRST CLUSTER TO A SECOND CLUSTER TO REASSIGN STORAGE AREAS FROM THE FIRST CLUSTER TO THE SECOND CLUSTER - Provided are a method, system, and article of manufacture for copying data from a first cluster to a second cluster to reassign storage areas from the first cluster to the second cluster. An operation is initiated to reassign storage areas from a first cluster to a second cluster, wherein the first cluster includes a first cache and a first storage unit and the second cluster includes a second cache and a second storage unit. Data in the first cache for the storage areas to reassign to the second cluster is copied to the second cache. Data in the first storage unit for storage areas remaining assigned to the first cluster is copied to the second storage unit. | 10-09-2008 |
20090177859 | METHOD, SYSTEM, AND PROGRAM FOR WRITE PROCESS MANAGEMENT - Provided are a method, system, and program for managing write processes in which a list of destination location identifiers for pending write operations is maintained in an array having an array pointer which identifies the next available entry of the array. In one embodiment, the array includes a stack of variable size. Adding a destination location identifier of a pending write operation increases the size of the stack. Removing a destination location identifier of a completed write operation reduces the size of the stack. A stack index may be incremented as write operation destination location identifiers are added and may be decremented as write operation destination location identifiers are removed from the stack. | 07-09-2009 |
20090300298 | MEMORY PRESERVED CACHE TO PREVENT DATA LOSS - A method, system, and computer program product for preserving data in a storage subsystem having dual cache and dual nonvolatile storage (NVS) through a failover from a failed cluster to a surviving cluster is provided. A memory preserved indicator is initiated to mark tracks on a cache of the surviving cluster to be preserved, the tracks having an image in an NVS of the failed cluster. A destage operation is performed to destage the marked tracks. Subsequent to a determination that each of the marked tracks have been destaged, the memory preserved indicator is disabled to remove the mark from the tracks. If the surviving cluster reboots previous to each of the marked tracks having been destaged, the cache is verified as a memory preserved cache, the marked tracks are retained for processing while all unmarked tracks are removed, and the marked tracks are processed. | 12-03-2009 |
20090300408 | MEMORY PRESERVED CACHE FAILSAFE REBOOT MECHANISM - A method, system and computer program product for preserving data in a storage subsystem having dual cache and dual nonvolatile storage (NVS) through a failover from a failed cluster to a surviving cluster, the surviving cluster undergoing a rebooting process, is provided. A memory preserved indicator associated with a cache of the surviving cluster is detected. The memory preserved indicator designates marked tracks having an image in an NVS of the failed cluster to be preserved through the rebooting process. A counter in a data structure of the surviving cache is incremented. If a value of the counter exceeds a predetermined value, a cache memory is initialized, and the marked tracks are removed from the cache to prevent an instance of repetitive reboots caused by a corrupted structure in the cache memory. | 12-03-2009 |
20100037226 | GROUPING AND DISPATCHING SCANS IN CACHE - A method, system, and computer program product for grouping and dispatching scans in a cache directory of a processing environment is provided. A plurality of scan tasks is aggregated from a scan wait queue into a scan task queue. The plurality of scan tasks is determined by selecting one of (1) each of the plurality of scan tasks on the scan wait queue, (2) a predetermined number of the plurality of scan tasks on the scan wait queue, and (3) a set of scan tasks of a similar type on the scan wait queue. A first scan task from the plurality of scan tasks is selected from the scan task queue. The scan task is performed. | 02-11-2010 |
20100191925 | DEFERRED VOLUME METADATA INVALIDATION - A method, system, and computer program product for managing modified metadata in a storage controller cache pursuant to a recovery action by a processor in communication with a memory device is provided. A count of modified metadata tracks for a storage rank is compared against a predetermined criterion. If the predetermined criterion is met, a storage volume having the storage rank is designated with a metadata invalidation flag to defer metadata invalidation of the modified metadata tracks until after the recovery action is performed. | 07-29-2010 |
20140082254 | RECOVERY FROM CACHE AND NVS OUT OF SYNC - For cache/data management in a computing storage environment, incoming data segments into a Non Volatile Storage (NVS) device of the computing storage environment are validated against a bitmap to determine if the incoming data segments are currently in use. Those of the incoming data segments determined to be currently in use are designated to the computing storage environment to protect data integrity. | 03-20-2014 |
20140082292 | EFFICIENT CACHE VOLUME SIT SCANS - A processor, operable in a computing storage environment, allocates portions of a Scatter Index Table (SIT) disproportionately between a larger portion dedicated for meta data tracks, and a smaller portion dedicated for user data tracks, and processes a storage operation through the disproportionately allocated portions of the SIT using an allocated number of Task Control Blocks (TCB). | 03-20-2014 |
20140082296 | DEFERRED RE-MRU OPERATIONS TO REDUCE LOCK CONTENTION - Data operations, requiring a lock, are batched into a set of operations to be performed on a per-core basis. A global lock for the set of operations is periodically acquired, the set of operations is performed, and the global lock is freed so as to avoid excessive duty cycling of lock and unlock operations in the computing storage environment. | 03-20-2014 |